The present invention relates to a thread wound golf ball containing a novel Wound Oriented Thermoplastic Elastomer Golf Ball Thread Structure, (hereinafter referred to as WOTEGBTS). In a preferred embodiment the WOTEGBTS consists essentially of threads comprising oriented polyether esters or oriented polyether amides optionally containing minor amounts of modifying polymers and other additives. The WOTEGBTS provides a thread wound golf ball with improved combinations of good spin for ball control on iron or wedge shots while providing for higher hardness and long travel with driver shots.
Golf balls containing WOTEGBTS are more easily manufactured, of high quality and high performance due to specific attributes of the WOTEGBTS. These attributes are: surprisingly high compressive resiliency; high tensile elasticity; superior strength; recycle ability; excellent durability; and high dimensional uniformity and precision compared with prior art golf ball thread rubber structures. In addition, WOTEGBTS can be readily engineered to have controlled mechanical property profiles, across the thread wound layer, as a function of radial distance from the golf ball center. These unprecedented property profiles can produce novel, different ball response characteristics as a function of the type of shot being played (i.e., type of shot meaning driver, iron or wedge or in mechanical terms essentially the force vector delivered by the club, the club impact area and club face angle).
The property profiles originate in one or a combination of design factors used to make the WOTEGBTS composition. The design factors, or design, together make up one aspect of the invention that is novel and useful and leads to surprising results. The factors that are engineered over the length of thread used in the WOTEGBTS, are: constant mechanical properties; controlled varying mechanical properties; a constant winding tension; a controlled varying winding tension; thread cross sectional shapes or profiles; constant cross sectional areas; controlled varying cross sectional areas. These novel property profiles were not possible with prior art thermoset rubber thread wound golf balls.
A thread wound golf ball is generally produced by winding thread rubber under tension around a center to form a thread wound core and then providing a covering on the thread wound core. The thread rubber requires high strength sufficient for tightly winding it on a center. The threads must also possess high impact rubber resilience in the stretched or wound condition sufficient for enhancing the flight distance.
U.S. Pat. No. 5,728,011 titled xe2x80x9cThread Wound Golf Ball and Process for Producing the Samexe2x80x9d gives a good description of thread rubber typically used, its limitations in terms of uniformity and the lengthy and complex process for making the vulcanized thermoset rubber threads.
Thread rubber used for a thread wound golf ball has generally been produced by molding a raw rubber material into a sheet having a predetermined thickness, winding the raw rubber sheet around a drum having a certain size, vulcanizing using a vulcanizer and cutting the vulcanized rubber sheet into a suitable width. The authors cite problems of frequent thread rubber breakage and the process constraints that lead to varying degrees of thread rubber vulcanization that lead directly to scatter in ball compression and scatter in flight distance.
The process whereby prior art rubber threads for golf balls are produced also relies upon cutting vulcanized rubber sheets into threads. The sheets are thin, often about 0.5 mm and it is difficult to produce these sheets with highly uniform thickness. This results in cut threads having significant variability in thickness. The cutting process is also limited in terms of the cross sectional geometry of the resulting thread to either essentially square or (more preferred) rectangular.
U.S. Pat. No. 4,783,078 xe2x80x9cWound Golf Ballsxe2x80x9d discloses a two stage winding process for the customary thermoset rubber threads to reduce breaks during thread winding for liquid center golf balls. This winding essentially varies the tensions along the length of thread rubber which changes the winding process to reduce thread breaks. No mention is made of providing an oriented thermoplastic thread wound structure with engineered properties along the length of the thread to adjust the ball performance by use of this method to accommodate both driver and iron/wedge shots.
Japanese Patent Publication JP 5,212,137 A2 discloses a method to fix the thread rubber on the center by adding a hot melt adhesive to the thread rubber to glue it to the center. It is not possible to fix a thermoset rubber thread to the center by melting a portion of the thread because thermoset rubber threads are cured and cannot be remelted and flowed.
U.S. Pat. No. 5,704,854: xe2x80x9cThree-piece Solid Golf Ballxe2x80x9d discloses an invention whereby a thermoplastic polyester elastomer is molded as a relatively thin, solid intermediate layer between the center and the cover to provide some of the control characteristics or spin response of a rubber thread wound golf ball with the durability of a two-piece ball. As a three-piece solid golf ball, it does not contain a thread wound layer. They make no mention or reference of using a wound oriented thermoplastic polyester elastomer golf ball thread structure as the intermediate layer.
U.S. Pat. No. 5,965,669: xe2x80x9cMulti-layer golf ball and compositionxe2x80x9d discloses a three-piece solid golf ball using a molded thermoplastic in the mantle layer where the preferred material is a polyetherester block copolymer with a specific gravity below 1.2. There is no mention of or reference of using a wound oriented thermoplastic polyester elastomer golf ball thread structure as the intermediate mantle layer.
The above-mentioned patents have improved the thermoset rubber thread wound golf balls and the three piece solid golf balls but still leave room to improve the combination of properties of spin receptivity of the wound balls in combination with the durability, uniformity and thermoplastic processing ease of the solid balls. The prior art discloses thermoset rubber thread wound balls and solid balls with molded thermoplastic elastomer layers. Nowhere has it been disclosed to use thermoplastic elastomer threads as a thread wound layer; moreover, nowhere has it been mentioned to use oriented thermoplastic elastomer threads as the wound layer. Specifically there is a need for a WOTEGBTS which: can be readily and consistently produced without the need for complex vulcanization processes; has highly precise dimensions; has high compressive resiliency and tensile elasticity; has precision controlled property profiles as a function of radial distance from the ball center; can be formed from threads of varying cross sectional geometry to tailor ball property response; can be recycled; and has higher strength and durability. The WOTEGBTS provides a thread wound golf ball with improved combinations of good spin for ball control on iron or wedge shots whilst providing for higher hardness and long travel with driver shots.
The Oriented Thermoplastic Elastomer Thread Wound Golf Ball invention includes Oriented Thermoplastic Elastomer thread wound structures with one or more of the following precision controlled, engineered compositional elements: constant mechanical properties; controlled varying mechanical properties; a constant winding tension; a controlled varying winding tension; thread cross sectional shapes or profiles; constant cross sectional areas; controlled varying cross sectional areas; threads wound at constant or varying tension; threads of various cross sectional shapes; threads of constant or varying cross sectional area; threads of constant or varying mechanical property profiles.
The invention also includes an oriented thermoplastic elastomer thread wound golf ball with high compressive resiliency and tensile elasticity. Generally, any thermoplastic elastomer or rubbery thermoplastic material capable of forming an oriented thread of sufficient structural integrity is useful in the invention. Also included in the invention are multi-component threads where at least one component is an oriented thermoplastic elastomer thread.
In a preferred embodiment, the thread wound structure or structures in the thread wound golf ball comprises: (a) 100 percent to 0 percent polyetherester or copolyetherester block copolymer based upon the weights of components (a) and (b); (b) 0 percent to 100 percent polyetheramide or copolyetheramide based upon the weights of components (a) and (b); (c) 0 parts to 50 parts by weight of other modifying polymers and additives based upon the sum weights of components (a) and (b).
In one embodiment the core is constructed by winding the oriented thermoplastic elastomer thread about itself. This can be done by first folding (winding) the thread(s) over itself several times and then winding the remaining thread(s) in a conventional manner.
In another embodiment the core is constructed by winding the oriented thermoplastic elastomer threads around a center or inner sphere of any dimension or composition, such as thermoset solid rubber sphere, a thermoplastic solid sphere, wood, cork, metal, or any material known to one skilled in the art of golf ball manufacture. The inner sphere could be a liquid filled sphere or shell such as a rubber sack, a thermoplastic or metallic shell design, in which the liquid could be of any composition or viscosity. It is feasible to construct such a center with a void or gas center. In another embodiment, the center can be filled with a liquid, a gel, a paste, a cellular foam, or a gas.
Finally, an outer cover is molded around the completed core (the core contains the rest of the ball which includes at least one oriented thermoplastic elastomer thread wound layer) to produce the ball. Any process that results in accurate and repeatable central placement of the core within the cover is acceptable. Generally, covers are applied by compression molding, injection molding, or casting cover material over the core.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is also capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting in any way the scope of this invention or claims.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may be readily utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions and methods insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the abstract is to enable the U.S. Patent and Trademark Office, International Patent Offices, PCT Patent Authorities, any and all National Patent Offices, and the public generally, and especially the scientists, engineers, and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection, the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by claims, nor is it intended to be limiting as to the scope of the invention in any way.
It is therefore an object of the present invention to provide a Oriented Thermoplastic Elastomer Thread Wound Golf Ball which has many of the advantages of the golf balls mentioned heretofore and many novel features that result in a Oriented Thermoplastic Elastomer Thread Wound Golf Ball which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art whether cited or referenced above or not, either alone or in any combination thereof.
It is another object of the present invention to provide a new and novel Oriented Thermoplastic Elastomer Thread Wound Golf Ball which may be easily and more efficiently manufactured, taught and marketed.
It is further object of the present invention to provide a new and novel Oriented Thermoplastic Elastomer Thread Wound Golf Ball which is of durable and reliable construction and method.
An even further object of the present to provide a new and novel Oriented Thermoplastic Elastomer Thread Wound Golf Ball which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is susceptible of low prices of sale to the consuming public, thereby making such Oriented Thermoplastic Elastomer Thread Wound Golf Ball economically available to the buying public.
Still yet another object of the present invention is to provide a new and novel Oriented Thermoplastic Elastomer Thread Wound Golf Ball which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith.
These together with other objects of the invention, along with the various features of novelty which characterize the invention, will be pointed out with particularity in the claims. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated preferred embodiments of the invention.